Wood block



\ c. w. ALLEN June 2, 1 931.

WOOD BLOCK Filed March 30, 1929 5 H0 M w J? 7 7 W .7 v 5 a f .9 I W A IT/ VFV W m 21--.? Llifiillg u a n a u L w H 7 0 {1| Ll {l 1 "1:11 -T/ 1}{1| J. t u u m m n n n r1 I l I 1-1.Fl ll|| 1 I II gwoenfo' dummy, v

' With these and other objects in view, my

Patented June 2, 1931 UNITED STATES cmnns w.

PATENT OFFICE x ALLEN, 01' MEMPHIS, TENNESSEE ASSIGNOR TO E. L. BRUCECOMPANY, 01.

umms, TENNESSEE, A CORPORATION OF DELAWARE woon nnoox Continuation ofapplloatlon Serial Il'o. 198,085, filed June ll, 1927. This applicationfiled March 80, 1929.

Serial No. 851,435.

My invention relates to wood block flooring and one of the objects is tofabricate a woo block, from a pluralitg1 of strips, that will retain itsshape and t at can e manufactured cheaply.

Another object is to provide a use for short pieces of floorin 1 In themanufacture of flooring, many s ort lengths are produced which can notwell be used by bui ders, because of the labor costs involved. In orderto utilize these short pieces, any scheme contemplated must have solittle manufacturing cost attached to it as that these short pieces canbe made saleable at a profit. I fabricate these short pieces intostructural units that are preferably square and securely bound to getherby metal ties fitting in registering grooves in the strips.

Such structural units may be laid directly on a wood or concretesubfloor-with an interposed cement, and according to my invention, theylie perfectly flat and fit closely to gether so that they can be laidvery rapidly.

The strips constituting the units are fastened together by metal tiesengaging transverse grooves, preferably but not necessarily on theunderside of the unit. When applied on the underside of the unit, thefastening means is so constituted that it will not project below theunder surface and the unit will lie absolutel flat without rocking ortilting.

A furt er object ofthe invention is to provide a groove for the metaltie into which it can be dropped, as differentiated from such a devicethat is inserted endwise into the groove, which is often inconvenient ifnot sometimes impossible. In this way, it is possible to use a presserwhich flattens out the tie from above and forces its edges into'tightcontact with the wood.

invention consists of certain novel and peculiar features ofconstruction and combination of parts, as will be hereinafter more fullydescribed and particularly pointed out in the claims. I

Referring to the drawings for amore complete disclosure of theinvention:

- Fig. 1 is a perspectiveof a block made up of flooring strips;

position Fig. 2 is a bottom plan view; Fig. 3 is an elevationillustrating one form of tie in initial position;

Fig. 4 is a similar view of such tie in final I Fig. 5 is an elevationof a modified form of tie in initial position;

Fig. 6 is a similar view of such tie in final position;

Fig. 7 is a detail view of the tie shown in Fig. 5; and

Fig. 8 is a detail view of a modified'form of tie.

Flooring strips as customarilymade have a groove llalon'g one edge and atongue 12 Q5 along the opposite edge. For making the block of myinvention, the flooring strips 13, 14 and 15 are first cut to the samelength. When making a block of, the type that has three grooves and asingle tongue, I take the individual strips so cut, and pass themthrough a machine that simultaneously cuts a groove 16 in each end and agroove 17 across the grain, in the back of the strip. These grooves maybe cut by rotary cutter heads op: erating on each end and in the centerof thestrip simultaneously. Cutting all the grooves at the same timemakes them more accurate. In making a block that has two tongues and twogrooves, a tongue and a groove would be cut at opposite ends of eachstrip instead of-a groove at each end as above explained. This onlynecessitates using a different ty e of cutter head for cutting a tongueinstead of a groove. I I

In usinga rotary cutter head, the sides of the roove 17 will necessarilybe cut parallel an at right angles to the face of the strip. Suchgrooves are most readily and cheaply formed from a quantity roductionstandpoint, but grooves of other s apes may be used if desired. a

The several pieces of wood 13, 14 and 15 having been sawed to thedesired length and ooved at the ends and on the underside, are aid flatwith the underside up, on a table and brought together by having a presson each side of the block to force the tongues 12 and grooves 11 of theseveral strips together and then, while under pressure, the metal tie 9should be of such gage as to provide a tie,

18 is dropped into position in the groove 17, as shown in Figs. 3 and 5.Just suflicient pressure is put on the strips to cause the groove jointsto fit tightly together, but without any substantial compression of thewood. If the wood in the strips is retained under too heavy com ressionin the finished block, any swelling o the strips due to moistureabsorption will cause the block to buckle.

Pressure is applied to the entire outer surface of the tie to flatten itout and to bring its edges into sufficiently tight contact with thesides of the groove so as to hold the strips rigidly in assembledrelationship. When using seasoned oak flooring strips, the wood is veryhard and unless the metal tie is pressed at every point, it will buckle.With a metal tie of the shapes shown, the edges of the tie will fit inthe angles of the groove 17 and when sufiicient pressure is put on thetie, these edges will bite or sink into the wood, and hold the piecessecurely together The tie is made preferably of malleable metal, such ascold rolled steel, andthe metal of sufficient stiffness so as to preventwar ing or other dis lacement of the strips in handling the blocii. Atie of the shape shown in 'Fi s. 3 and 4 will be stiffer than a tie thatwould be fiat when in final position. When provided with a rib 19 asshown In Figs. 5,

6 and 7, additional stiffness will be given to the tie.

When the tie is in final position, no art of it should project beyondthe plane 0 the back of the block; the reason for this being that theblocks are preferably laid direct- 1y on a level subfloor and in contactwith it, which could not be done if there were any projections on thebottomof the block.

Teeth 20 may be provided along the edge of i the tie to facilitatebiting into the wood.

Other forms of ties than those shown and functioning in substantiallythe same manner will readily suggest themselves to those skilled in theart.

While the sides of the groove 17 are shown at right angles to the faceof the block and edges of the groove bite into the wood. In

while this is the preferred form, it is clear that substantially thesame results will be attained, if these sides should slope slightlytowards or away from each other and the tie is dropped into position andthen flattened out by pressing.

In the smaller sizes of blocks, a single tie and groove on the undersidewill be sufiicient, but with the larger sizes more than one tie andgroove may be used.

There is a decided advantage in dropping the ties into the grooves,rather than threading them in endwise, and also in having the view ofthe fact that the grooves 17 are cut in the individual strips beforeassembling,

case the tie should not be so deep as to contact with the tongue whichenters that groove. 6

After the block has been assembled, it is then subjected to awaterproofing treatment, by impregnating with a suitable oleagenouscomposition, so as to prevent, or at least retard, moisture absorption.Unless subjected to such treatment, the block may warp and not remainperfectly flat; or the change of shape of the individual strips maythrow the block out of square. The advantage of preventing theseobjectionable features are twofold 1) that the block will remain inshape during transit and storage prior to use; (2) that it will remainin shape after being laid in the completed floor.

From the above description, it will be seen that I provide a fabricatedblock that can be manufactured cheaply from short strips of' flooringthat would otherwise be waste or I of little value; that by using astiff metal tie as illustrative and not restrictive, reference being hadto the appended claims rather than to the foregoing description toindicate the $00 e of the invention.

his application is a continuation of my application Serial N 0. 198,085,filed June 11, 1927.

. I claim:

1. A structural unit comprising a plurality of strips of wood havin in asurfacethereof a groove with parallel sides at right an les to thesurface, and a metallic holder lying at i the bottom of the roove withits edges sunk into the wood at the. angles of the groove.

2. A structural unit comprising a plurality of stri s of wood'unitedalong their longitudinafedges, by a tongue. and groove joint, a groovecut transversel of the-grain of the stri s, a stiff metallic tie in theroove, the sai tie having its edges forced 1nto biting contact with t ewood, the tie being ofsufiicient stiffness to prevent warping ordisplacement of the strips relative to each other, .the contact of thetie with the wood being sufficiently tight to hold the strips rigidly inas 1 semhledrelationship, the-said tie'heing 'ent 4 tirely within'theouter-surfaces of the umt.

' 3. A structural unit formed of assembled stripS of wood free fromwarping co'mprism the combination to prevent warping o I tightly-fittingtongues and groove joints between the ad acent strips, a groovecrosswise of the strips, a stiff metallic'tie in the groove embedded inthe wood and in cooperation 10 with the said tongues and groovespreventing movement of the stri s in all directions relative to eachother, t e said wood being impregnated with a waterproofing composition.

4. A structural unit comprising a pluralit 15 of strips of woodvunitedalong then long1- tudinal edges by a tongue and groove joint, an 0 engisoove cut tran'sversely of the grain of t e strips, a stifi metallictie in the said grooveand embedded in the wood, and in cog operationwith the'said tongues and grooves,

preventing movement of the-strips in all 'directions relative to eachother.'

5. A structural unit comprising a plurality of strips of wood unitedalong their edges by 25 atongueauid groove joint, an open groove withparallel sides out transversely of the grain of the strips, a stiffmetallic tie in the said groove and inforced tight contact with the woodand in cooperation with the said '30 ton esand grooves, preventingmovement of t estrips in all directions relative to each other. v I

I In testimony whereof I aflix my si 'ature. 5 7 CHARLES W. EN. 3 r v I

